Multilayer Substrate With Built-In Capacitors, Method For Manufacturing The Same, And Cold-Cathode Tube Lighting Device

Abstract

For the purpose of lighting multiple cold-cathode tubes at uniform luminance using a cold-cathode tube lighting device incorporating a multilayer substrate with built-in capacitors through a common power source and downsizing the cold-cathode tube lighting device, the multilayer substrate with built-in capacitors comprising at least four conductor layers overlaid is formed by heating and pressing dielectric layers, on one side of each of which a conductor layer is formed, to both sides of a dielectric layer, on both sides of which a conductor layer is formed, respectively, with bonding layers P 1 and P 2 interposed therebetween and by press-bonding these layers mutually, and specific conductor layers are electrically connected using connection parts formed on the inner faces of through holes.

1 . A multilayer substrate with built-in capacitors having at least four conductor layers overlaid via dielectric layers, comprising at least: 
 a first member on which a first conductor layer having a predetermined conductor pattern is overlaid on one face of a first dielectric layer,    a second member having a second conductor layer and a third conductor layer each having a predetermined conductor pattern and overlaid on both faces of a second dielectric layer, respectively,    a third member having a fourth conductor layer having a predetermined conductor pattern and overlaid on one face of a third dielectric layer,    a first bonding layer disposed between the other face of said first dielectric layer and one face of said second member so as to bond the faces mutually, and    a second bonding layer disposed between the other face of said third dielectric layer and the other face of said second member so as to bond the faces mutually, wherein    specific conductor patterns are connected using the connection parts of through holes formed at predetermined positions in said multilayer substrate with built-in capacitors, thereby forming multiple capacitor blocks among said conductor layers.    
     
     
         2 . The multilayer substrate with built-in capacitors according to  claim 1 , wherein said multiple blocks are connected in series using said conductor patterns via said connection parts of said through holes.  
     
     
         3 . The multilayer substrate with built-in capacitors according to  claim 1 , wherein said multiple blocks are connected in parallel using said conductor patterns via said connection parts of said through holes.  
     
     
         4 . The multilayer substrate with built-in capacitors according to  claim 1 , wherein said conductor patterns of every other layers overlaid in said blocks have substantially the same shape.  
     
     
         5 . The multilayer substrate with built-in capacitors according to  claim 1 , wherein said conductor patterns of every other layers overlaid in said blocks have substantially same shape, specific conductor patterns of every other layers are connected using said connection parts of through holes so as to form a comb structure, and multiple interlayer capacitances are connected in series.  
     
     
         6 . The multilayer substrate with built-in capacitors according to  claim 1 , wherein said respective bonding layers are made of an epoxy-based synthetic resin containing a reinforcing material formed of carbon fibers.  
     
     
         7 . The multilayer substrate with built-in capacitors according to  claim 1 , wherein said respective dielectric layers are formed of an epoxy resin substrate containing glass fibers as a reinforcing material.  
     
     
         8 . The multilayer substrate with built-in capacitors according to  claim 1 , being used for a lighting device having multiple cold-cathode tubes arranged in parallel, and disposed so as to be orthogonal to the central axes of said cold-cathode tubes.  
     
     
         9 . A method for manufacturing a multilayer substrate with built-in capacitors having at least four conductor layers overlaid via dielectric layers, comprising at least: 
 a step of producing a first member on which a first conductor layer having a predetermined conductor pattern is overlaid on one face of a first dielectric layer,    a step of producing a second member having a second conductor layer and a third conductor layer each having a predetermined conductor pattern and overlaid on both faces of a second dielectric layer, respectively,    a step of producing a third member having a fourth conductor layer having a predetermined conductor pattern and overlaid on one face of a third dielectric layer,    a step of disposing a first bonding layer between the other face of said first dielectric layer and one face of said second member,    a step of disposing a second bonding layer between the other face of said third dielectric layer and the other face of said second member,    a step of carrying out heating and pressing in a direction of sandwiching said first dielectric layer, said second dielectric layer and said third dielectric layer via said first bonding layer and said second bonding layer so as to bond said layers mutually,    a step of forming through holes at predetermined positions of specific conductor patterns, and    a step of forming multiple capacitor blocks among said conductor layers by forming connection parts on the inner faces of said through holes and by electrically connecting specific conductor patterns.    
     
     
         10 . The method for manufacturing a multilayer substrate with built-in capacitors according to  claim 9 , wherein said multiple blocks are connected in series using said conductor patterns via said connection parts of said through holes.  
     
     
         11 . The method for manufacturing a multilayer substrate with built-in capacitors according to  claim 9 , wherein said multiple blocks are connected in parallel using said conductor patterns via said connection parts of said through holes.  
     
     
         12 . The method for manufacturing a multilayer substrate with built-in capacitors according to  claim 9 , wherein said conductor patterns of every other layers overlaid in said blocks have substantially the same shape.  
     
     
         13 . The method for manufacturing a multilayer substrate with built-in capacitors according to  claim 9 , wherein said conductor layers are formed by evaporation of metal thin films.  
     
     
         14 . The method for manufacturing a multilayer substrate with built-in capacitors according to  claim 9 , wherein said respective bonding layers are made of an epoxy-based synthetic resin containing a reinforcing material formed of carbon fibers.  
     
     
         15 . The method for manufacturing a multilayer substrate with built-in capacitors according to  claim 14 , wherein said respective dielectric layers are formed of an epoxy resin substrate containing glass fibers as a reinforcing material.  
     
     
         16 . A cold-cathode lighting device equipped with: 
 a multilayer substrate with built-in capacitors, having multiple ballast capacitors formed of at least four conductor layers overlaid via dielectric layers, and    a low-impedance power source, having a low output impedance, for supplying power to cold-cathode tube via said ballast capacitors,    said multilayer substrate with built-in capacitors, having at least four conductor layers overlaid via dielectric layers, comprising at least:    a first member on which a first conductor layer having a predetermined conductor pattern is overlaid on one face of a first dielectric layer,    a second member having a second conductor layer and a third conductor layer each having a predetermined conductor pattern and overlaid on both faces of a second dielectric layer, respectively,    a third member having a fourth conductor layer having a predetermined conductor pattern and overlaid on one face of a third dielectric layer,    a first bonding layer disposed between the other face of said first dielectric layer and one face of said second member so as to bond the faces mutually, and    a second bonding layer disposed between the other face of said third dielectric layer and the other face of said second member so as to bond the faces mutually, wherein    specific conductor patterns are connected using the connection parts of through holes formed at predetermined positions in said multilayer substrate with built-in capacitors, thereby forming multiple capacitor blocks among said conductor layers.    
     
     
         17 . The cold-cathode lighting device according to  claim 16 , equipped with said multilayer substrate with built-in capacitors, wherein said multiple blocks are connected in series using said conductor patterns via said connection parts of said through holes.  
     
     
         18 . The cold-cathode lighting device according to  claim 16 , equipped with said multilayer substrate with built-in capacitors, wherein said multiple blocks are connected in parallel using said conductor patterns via said connection parts of said through holes.  
     
     
         19 . The cold-cathode lighting device according to  claim 16 , equipped with said multilayer substrate with built-in capacitors, wherein said conductor patterns of every other layers overlaid in said blocks have substantially the same shape.  
     
     
         20 . The cold-cathode tube lighting device according to  claim 16 , wherein said low-impedance power source is mounted on a substrate different from said multilayer substrate with built-in capacitors.  
     
     
         21 . The cold-cathode tube lighting device according to  claim 16 , having multiple cold-cathode tubes arranged in parallel, said multilayer substrate with built-in capacitors being disposed so as to be orthogonal to the central axes of said cold-cathode tubes, wherein a power source circuit for said respective cold-cathode tubes is provided in a different region.  
     
     
         22 . The cold-cathode tube lighting device according to  claim 16 , wherein, among said multiple conductor layers in said multilayer substrate with built-in capacitors, the conductor layer nearest said cold-cathode tube is connected to the electrode of said cold-cathode tube, and the conductor layer farthest from said cold-cathode tube is connected to said low-impedance power source.  
     
     
         23 . The cold-cathode tube lighting device according to  claim 16 , wherein said low-impedance power source includes a transformer, and said transformer comprises a core, a primary winding wound around said core and a secondary winding wound around the inside or outside or both the inside and outside of said primary winding.  
     
     
         24 . The cold-cathode tube lighting device according to  claim 16 , wherein said low-impedance power source is configured so as to have a power transistor.